The California Air Resources Board approved sweeping new emissions regulations affecting heavy-duty trucks sold in the state. An organization representing truck and engine makers decried the new rule.

The Omnibus Low-NOX Rule, approved by CARB on Aug. 28 will require engine NOx emissions to be cut to approximately 75% below current standards beginning in 2024, and 90% below current standards in 2027.

The rule also places nine additional regulatory requirements on new heavy-duty truck and engines. Those additional requirements include a 50% reduction in particulate matter emissions, stringent new low-load and idle standards, a new in-use testing protocol, extended deterioration requirements, a new California-only credit program, and extended mandatory warranty requirements.